Molecular Basis of Inheritance Questions and Answers

DNA from a newly discovered virus was purified, and UV light absorption was followed as the molecule was slowly heated. The absorbance increase at the melting temperature was only 10%. What does this result tell you about the structure of the viral DNA?

What binds to a stop codon to end translation? Nothing binds to stop codons. A tRNA that is specific for that stop codon sequence. The last amino acid in the protein. A release factor protein.

What is the amino acid sequence of the protein coded from the following mRNA molecule? GLU-ASN-PHE-PRO LEU-LEU-LYS-GLY LEU-PHE-PHE-LEU LEU-LEU-ASN-GLY CUUUUAAAGGGG

The process of making DNA is referred to as _____ Coding DNA into RNA is ----- while RNA being coded to proteins is ______ ::Translation DNA synthesis transcription

genes control the development and differentiation of body segments, and the genes/elements which are near them in an animal genome have a distinct role in t body segments. Lactose Hox (Homeobox) FOXP2 Pseudogenes

The wildtype DNA has the following sequence: ACGATTACGAA It has undergone mutation and it now has the sequence (mutation is underlined): ACGACGCACGAA answer questions a-e below in the textbox under this question (1 pt each). a. what is this type of mutation called? b. this type of mutation results in a protein that is shorter than usual. True or False c. what mutagen caused this mutation? d. extra credit (optional): what does this mutagen do to the DNA e. extra credit (optional): can this mutation be repaired- just answer yes (name the mechanism if you answer yes) or no.

The point of the Deleterious Mutation Hypothesis was that individuals which have a genotype will be removed from the reproducing population via sex (if the recessive mutation is deleterious) and thus the fitness of the population will not deteriorate and may improve over time. Homozygous Dominant Heterozygous Homozygous Recessive Insertion/Deletion 4 points

The deposition of Eumelanin in human skin (and thus the light dark variation of human skin) generally trends to provide greater pigmentation closer to the equator (where there is more cancer causing Ultraviolet light) and less deposition at greater latitudes (where less UV light is provided by the sun). If humans variation in this factor is based upon the deposition of eumelanin providing a survival advantage in areas and not so much of an advantage in other areas, then we could say this variation across the habitat of humanity (the land of Earth) is an example of...

In bacteria (prokaryotic cells), the coding region/reading frame portion of the gene... serves as the template for making mRNA (ie-bases in this region are read by RNA polymerase to make mRNA) contains both intron and exons is the binding site for RNA Polymerase is the binding site of the repressor is the end of the gene

true or false. transcription is the FIRST stage of gene expression; it involves DNA polymerase reading the gene to make mRNA false true

the DNA of a virus inserts into the reading frame (coding region) of a gene in the host cell. This is most likely to result in ____________ mutation, which is likely to be _______ (more or less-pick one) disruptive to protein structure than a single missense mutation. For each choice, the first part goes into the first space; the 2nd part goes into the 2nd space. non-sense; more silent; less nonsense; less frameshift; more frameshift; less silent; more

genetic information... does NOT specify/determine observable characteristics of the cell is found in the backbone of DNA is found in the base sequence of the DNA is information which the organism does NOT need for its activities and survival contains information about proteins ONLY

Visible traits are produced: only when mutation occurs when the cell's proteins are NOT functioning/doing their jobs as a result of replication during the repair of DNA damage as a result of expression

an mRNA molecule has the sequence 5'UCA AUG UGC CAC3. Which of the following best describes the tRNA that binds to the second/2nd codon of this mRNA? Has the anticodon UAC and the amino acid methionine has anticodon AUG and the amino acid methionine has anticodon TAC and the amino acid tyrosine It can have any anticodon and any amino acid Has the anticodon ACG and the amino acid cysteine

the nucleic acid of the bacteriophage is replicated by: Host cell DNA polymerase host cell RNA polymerase NA (neuroaminidase) Viral RNA polymerase Reverse transcriptase

Which of the following does NOT apply to (or describe) the structure of RNA? the sugar of one nucleotide is joined to the phosphate of another nucleotide to make a RNA "strand" ONE molecule of RNA is made of two strands (polymers of nucleotides) some of the nucleotides that make up RNA have base "U" instead of base "T" some RNA molecules can be a part of the ribosome; some RNA also participate in translation RNA is made of nucleotides that contains the sugar ribose

you introduced mutations into bacteria. However, the bacteria have the same characteristics as before (i.e., the characteristics of the bacteria did not change). What kind of mutations do the bacteria have? missense frameshift silent nonsense base insertion

DNA replication is "semi-conservative" this means... in replication, the newly made strand is half DNA and half RNA the cell only copies or replicates half of the total number of DNA molecules it has during cell division RNA is the template for making new DNA in the daughter/new DNA made during replication, one strand is newly made; the other strand comes from parental DNA (half of the daughter DNA is new, half of it is old) Replication requires a primer

You can thank hydrogen bonding for holding together your DNA! True False

The origin is the site on the DNA: that marks the beginning of a gene where RNA polymerase binds to DNA (gene)- i.e., it is the binding site for RNA polymerase where transcrption begins where helicase binds to DNA and where replication begins where DNA polymerase binds to DNA where translation begins

which of the following causes transcription to end? ribosome reads a STOP codon RNA polymerase binds to the promoter RNA polymerase leaves promoter and goes into the reading frame RNA polymerase reaches the terminator ribosome binds to mRNA

which of the following does NOT occur when the expression of the operon genes is turned ON? transcription and translation both occur repressor is released/removed from the operator (ie- repressor is NOT bound to the operator) repressor binds to operator RNA polymerase binds to promoter the proteins specified by operon genes are made

during DNA replication, the new strand is always 100% DNA. True False

What is the role of mRNA? serves as "instructions" read by the ribosome to make protein it helps to control transcription by binding to the repressor brings the correct amino acid to the ribosome makes polypeptide (joins amino acids together) is the "skeleton" of the ribosome

Mutation in a gene that specifies a protein always results in: production of non-functional proteins changing the base sequence of mRNA changing the amino acid(s) found in the protein harming the organism/cell changing the protein's shape/structure

Please refer to the passage 86 and image to help you answe. this question. Where does the new protein end up after being released by the ribosome? A. in the nucleus B. in the cytoplasm C. in the cell membrane Translation is the process by which mRNA is translated into protein using tRNA. Translation is the final process involved in creating proteins. Once the "stop" codon is read, translation stops and the new protein is released from the ribosome as the ribosome breaks apart.

Which of the following share the same genetic code? a father and child b siblings c identical twins d mother and child

At the end of DNA replication, there should be a total of..... A. 8 SINGLE strands of DNA B. 2 DOUBLE stranded DNA helixes C. 5 DOUBLE stranded DNA helixes D. 10 SINGLE strands of DNA

What causes a gene to be passed on to offspring? A. an organism that has a successful trait and survives to pass it to offspring B. if an organisms has a certain unsuccessful trait then that specific trait won't be passed on C. it is completely random within a population which genes do and don't get passed on

Match the enzyme to the correct function in the HIV life cycle takes viral DNA and inserts it into the host chromosome cuts the polyprotein into functional proteins makes a DNA copy of the viral genome from viral RNA 1. protease 2. reverse transcriptase 3. integrase 4. neuramidase 5. lysozyme 6. nuclease

Most of the processes required for maturation of eukaryotic mRNAs occur cotranscriptionally. Which of the processes below occurs post-transcriptionally (i.e. after RNA synthesis is complete)? a. Capping b. Poly-adenylation c. Intron removal d. mRNA editing e. Splicing

Which type of mutation is exemplified by this statement? A base substitution mutation resulted in conversion of an AAA codon to GAA. AAA codes for lysine (a basic amino acid); GAA codes for glutamic acid (an acidic amino acid). A. sense mutation B. nonsense mutation C. missense (conservative) mutation D. missense (non-conservative) mutation E. silent mutation

In the 1940s, the scientist J. B. S. Haldane linked many human red blood cell disorders with the tropical regions where malaria occurs. Haldane hypothesized that the widespread presence of these red blood cell disorders, as well as traits that protect individuals from malaria, were the result of natural selection. Haldane's hypothesis was later confirmed by the research of A. C. Allison. In areas where malaria is widespread, what is the resistance to malaria carried by individuals the result of? a vaccine against malaria the individuals' genetic composition antibiotic medications the individuals' behavior in avoiding those with the infection

39. Label each of the following with the correct category of enzyme (constitutive enzyme) - 10 points enzyme or inducible/repressible Amylase: Helicase: Penicillinase: ATP Synthase: Lipases: DNA Polymerase: Lactose Fermentation: Maltase:

A dominant allele only shows up in the physical when it is homozygous. True False

All of the following are considered post- transcriptional modifications that occur in the nucleus EXCEPT (A) 5' capping with methylated guanines. (B) the addition of a 3' poly-adenine tail. (C) the excision of introns from mRNA via spliceosome formation. (D) mRNA attachment to polyribosomes. (E) stabilization of mRNA by snRNPs.

You would like to amplify the following genomic DNA segment using some combination of the four primers (P, Q, R, and S) that you have in your possession. The primers are already aligned in the same positions as the template sequence for ease of reading.

What is the catalase test? Coagulase test? What does it mean to be: Catalase + Catalase Coagulase + Coagulase - When working with an unknown that may be Staphylococcus two tests help? (but you are not sure), how can the Give step by step detail of how to determine you are dealing with Staphylococcus and not an organism such as Streptococcus (next week topic).

Suppose that in gerbils, there are two alleles for fur color. Gerbils with a dominant allele are brown, and black fur color is recessive. If 35% of a gerbil population has black fur, what percent is expected to be heterozygous? 17% 41% 48% 59%

A bacterium can make the amino acid glycine or absorb it from its surroundings. A biochemist found that glycine binds to a repressor protein and causes the repressor to bind to the bacterial chromosome, turning off an operon. If it is like other operons, the presence of glycine will result in the The breakdown of glycine Inhibition of bacterial cell division Cessation of the synthesis of glycine Manufacture of the repressor protein

If lactose is present in the environment of an E. coli cell: The lactose will trigger increased replication of the gene for B-galactosidase The lactose will bind to the repressor protein causing it to change shape and be released from the operator region The lac operon will hydrolyse the lactose into ß-glucose and B-galactose The lactose will bind to the repressor protein causing it to change shape so that it can bind to the regulator gene in the operon

Which of the following is NOT part of the holoenzyme responsible for replication in bacteria? a. DNA polymerase I b. Clamp loader C. DNA polymerase III d. Sliding clamp

Eukaryotic cells use multiple methods to regulate the amount of each protein in the cell. For each of the following scenarios, choose whether it would be better for the cell to regulate expression at the level of transcription, translation, or post-translation and explain why you made that choice. A) a metabolic enzyme that is only necessary when certain nutrients are present B) an enzyme involved in initiation of apoptosis that helps with cutting chromosomes into small pieces

Using a well-labeled diagram and a narrative, describe the regulation of the lac operon when glucose levels are low and lactose is present. Compare/contrast this with initiation of transcription in a eukaryotic gene.

Which of the following statements are correct with respect to protein synthesis? Check all that apply. The protein chain always stops with valine. Many amino acids can be synthesized using one of two different codons. Uracil is one of the bases present in a DNA strand. If the codon AUG does not appear at the 5' end of mRNA, it codes for the amino acid methionine. A stop codon not required to stop protein synthesis. Protein synthesis always starts with an initiation codon.

What is the main difference between the two main categories of point mutations? Frameshift mutations change the structure of the chromosome, but base pair mutations only change the genetic code Base pair mutations do not change the reading frame of the DNA Frameshift mutation are often silent Frameshift mutations will cause a change in the phenotype, but base pair mutations will not

Which of the following is not associated with a bacterial ribosome? Select one: a. It is a 70s holoenzyme. b. It has a peptide (P) site. c. It has an exit site. d. Its small subunit provides the enzymes for making peptide bonds. e. It has an amino acid (A) site.

A positive direct ELISA result requires Select one: a. one known antibody, one unknown antibody, and an unknown antigen. b. one known antibody, one unknown antibody, and a known antigen. c. two known antibodies and one known antigen. d. two known antibodies and one unknown antigen.

What is the role of mRNA? It is involved in the translation of mRNA It is the template of translation It is involved in regulating gene expression It is involved in modification of mRNA molecules

Supposed a tRNA molecule bearing the anticodon for cysteine, and with a cysteine bound to it, is chemically treated as to change the cysteine to alanine (the tRNA molecule and the anticodon remain unaltered). Which of the following is likely to be true? Transcription would stop when the tRNA molecule entered the ribosome Cystine would continue to be brought to the ribosomes by this tRNA Alanine would be incorporated in to be peptide in place of cystine The amino acid bound to this tRNA would not be added to the growing polypeptide